AFOQT Practice Test

What does an increase in amplitude indicate about a sound wave?

1. The sound is of lower pitch

2. The sound is softer

3. The sound is louder

4. The sound has a higher frequency

The correct answer is: The sound is louder

An increase in amplitude of a sound wave signifies that the sound is louder. Amplitude refers to the maximum extent of a vibration or oscillation, which in the context of sound waves relates to the pressure variation that creates sound. As the amplitude increases, the energy carried by the sound wave also increases, leading to a greater perceived loudness to the human ear. Essentially, louder sounds have greater amplitude, while softer sounds have lower amplitude. In contrast, the other options do not accurately reflect what an increase in amplitude indicates. For instance, changes in pitch relate to frequency rather than amplitude; higher frequencies result in higher pitches. Similarly, an increase in amplitude does not equate to a softer sound, nor does it imply anything about the pitch of the sound. Thus, the key takeaway is that an increase in amplitude directly correlates with an increase in loudness.